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Returning a boolean from a Bash function
I want to write a bash function that check if a file has certain properties and returns true or false. Then I can use it in my scripts in the "if". But what should I return?
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Is using a lot of static methods a bad thing?
I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be ...
Summarizing multiple columns with dplyr? [duplicate]
I'm struggling a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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How can I list ALL DNS records?
Is there any way I can list ALL DNS records for a domain?
8 Answers
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What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
Please help me understand where to use a regular JOIN and where a JOIN FETCH.
5 Answers
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Generating a UUID in Postgres for Insert statement?
My question is rather simple. I'm aware of the concept of a UUID and I want to generate one to refer to each 'item' from a 'store' in my DB with. Seems reasonable right?
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What is the difference between supervised learning and unsupervised learning? [closed]
In terms of artificial intelligence and machine learning, what is the difference between supervised and unsupervised learning?
Can you provide a basic, easy explanation with an example?
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How to force use of overflow menu on devices with menu button
I'd like to have all of the menu items that don't fit into the ActionBar go into the overflow menu (the one that is reached from the Action Bar not the menu button) even on devices that do have a Menu button . This seems much more intuitive for users than throwing them into a separate menu list th...
How to make a HTML Page in A4 paper size page(s)?
Is it possible to make a HTML page behave, for example, like a A4-sized page in MS Word?
15 Answers
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How to handle :java.util.concurrent.TimeoutException: android.os.BinderProxy.finalize() timed out af
We're seeing a number of TimeoutExceptions in GcWatcher.finalize, BinderProxy.finalize , and PlainSocketImpl.finalize . 90+% of them happen on Android 4.3. We're getting reports of this from Crittercism from users out in the field.
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